May 29, 2008

In the X-Men comics, the superhero Wolverine is armed with three sharp claws on each arm. They extend through the skin of his hand, and the resulting wounds are closed by up his superhuman ability to heal. Now, in a bizarre case of life imitating art, scientists from Harvard University have discovered that a group of African frogs use similar weapons.

The frogs defend themselves with sharp bone claws on their hind feet but to do so, the animals have to drive the claws through their own skin. It's an extreme defence that is completely unique in the animal world.

The clawed frogs belong to a family called Arthroleptidae that were discovered in Central Africa more than a century ago. At first, people wondered if the claws just stuck through the skin as a side effect of the preservation process. Alternatively, the frogs may have used them to grip or climb. Their true function as defensive weapons only became clear when naturalists first described actually picking up and handling live animals.

Doing so is a mistake, and anyone who makes it is punished with a series of deep, bleeding wounds inflicted by the struggling animal as it kicks out violently with its claws. The ability is well known to the people of Cameroon, who only ever hunt the frogs with machetes or spears.

May 28, 2008

WEDNESDAY, May 28 (HealthDay News) -- Children who are exposed to lead at a young age are more likely to be arrested later in life.
A study in the May 27 issue ofPLoS Medicineis the first empirical evidence that elevated blood lead levels, both in the pregnant mother and in the child, are associated with criminal behavior in young adulthood.
"I never would have thought that we would be seeing these effects into the later 20s," said study co-author Kim Dietrich, a professor of environmental health at the University of Cincinnati. "I'm actually quite astounded and quite worried about this. Although lead levels have been going down in this country, a large proportion of the population now in their 20s and 30s had blood levels in this neurotoxic range."
Childhood lead exposure has been linked with anti-social behavior, lower IQ, attention deficits, hyperactivity and weak executive control functions, all of which are risk factors for future delinquent behavior (attention-deficit hyperactivity disorder, in particular, is a risk factor for adult criminal behavior).

Each year in Michigan an estimated 22,000 children are lead-poisoned. About two-thirds of them live in Detroit. Lead is of greatest threat to children under age 6. Their neurological systems are developing and they are more likely to put contaminated objects into their mouths. Lead poisoning causes permanent brain damage.

May 26, 2008

The direct cost to the US government of the war and occupation of Iraq — counting only funds appropriated by Congress — so far runs to roughly $523Bn.

However, that's the direct cost — money directly spent on the project. There are indirect costs, too: Joseph Stiglitz estimates the true cost of the war to be $3Tn to the United States, and $3Tn to the rest of the global economy. These are indirect costs, and factor in the long-term additional expenses that the war has accrued — everything from caring for brain-damaged soldiers for the next 50 years through to loss of economic productivity attributable to instabilities in the supply of oil from Iraq.

We can tap-dance around the indirect costs, but the direct costs (that headline figure of $523Bn) are inarguable.

So. What fun boondoggles could we have bought with either $523Bn (at the low end) or $6Tn (at the high end)?

NASA have plans for a manned Mars expedition based on the Ares spacecraft they're developing as a replacement for the Space Shuttle. Price estimates vary from $20Bn (presumably for a single round-trip) to $450Bn (presumably for a single round trip plus all the externalities, like developing the spacecraft and equipment and conducting a thorough prior reconnaissance using unmanned landers).

Either way, the direct costs of the Iraq war exceed the maximum cost estimate for a manned Mars expedition, infrastructure and all, by 20%. If we take $20Bn as the cost per mission and $450Bn as the cost to develop the technology to go there, the direct cost of the Iraq war would be sufficient to develop a gold-plated Mars expeditionary capability and send six crews of astronauts to Mars (and bring them back afterwards).